Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology OCR GCSE > B2.2 Size > Flashcards

B2.2 Size Flashcards

You may prefer our related Brainscape-certified flashcards:
GCSE Geography - AQA flashcards AP® Biology flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route A flashcards GCSE Religious Studies - Edexcel Route A flashcards GCSE Religious Studies - Eduqas Route B flashcards Biology 101 flashcards
1
Q

Surface area to volume ratio

A

Surface of an area per unit volume of an object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Format surface area to volume ratio should be presented in

A

Ratio
Surface area : volume
It should be simplified so volume = 1cm³

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why a tapeworm can rely upon diffusion alone to provide nutrients, where as multicellular organisms cannot

A

The larger the surface area to volume ratio the more easily and quickly nutrients can diffuse, as diffusion ratio is small e.g the tape worm

Increase size of organism = decrease surface area to volume ratio,
therefore diffusion distance becomes to great to allow an organism to meet the cells’ demands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Examples of adaptations to animal cells to improve surface area to volume ratio

A

Villi - intestines

Microvilli - Cilliated epithelial cells lungs

Alveoli - spherical shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Adaptations to plants to increase surface area to volume ratio

A

Broad flat leaves - increase SA for capturing light & gaseous exchange via the stomata

Root hair cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Adaptations of the lungs to maximise the rate at which oxygen enters the body

A

Single cell wall
Ventilation moves air in and out of lungs to maintain concentration gradient
Capillary network means good blood supply, which maintains concentration gradient
Spherical shape increases surface area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Adaptations of villi to maximise rate of diffusion and active transport in the small intestine

A

Single cell wall
Capillary network means good blood supply, which maintains concentration gradient
Fingerlike shape increases surface area
Microvilli increases surface area further
Many mitochondria to provide energy for active transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why transport systems are needed

A

To transport a substance to where it is needed once it has diffused

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Transport systems in humans

A

Respiratory

Circulatory

Digestive

Endocrinology

Nervous

Urinary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the circulatory system

A

Heart and blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Circulatory system of a fish compared to human circulatory system

A

Fish have a single circulatory system, humans have a double circulatory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

State difference between oxygenated and deoxygenated blood

A

Oxygenated = high levels of oxygen
Deoxygenated = low levels of oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name the the three types of blood vessel shown below.
/ / /.:. ./ / /
◎ / ◎./ ◉/
[x2] [x2000] [x2]
A B C

A

A = vein
B = capillary
C = artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Name adaptations of the three blood vessels

A

Vein: thin outer wall, thin layer of muscle and elestic fibres, large lumen
Capillary: very small lumen, single cell wall
Artery: thick outer wall, thick layer of muscle and elestic fibres, small lumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why humans have a double circulatory system

A

Consists of 2 circuits joined together
First circuit pumps deoxygenated blood to lungs to take in oxygen, and then returns oxygenated blood to heart
Second circuit pumps oxygenated blood all around the other organs of body and returns deoxygenated blood to heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Benefits of having a double circulatory system

A

Deoxygenated and oxygenated blood does not mix
Blood is under higher pressure as it does not have to travel as far
High pressure means the materials are transported around the body faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Difference between cardiac muscle and the muscles in the rest of your body

A

Heart is made of cardiac muscle that contracts without recieving nerve impulses from our brain
Muscle in the rest of your body (e.g in your arm) require a nervous signal to stimulate contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Parts of a heart

. Pulmonary vein
I———————->LUNGS—————————
Pulmonary I ┌──────-─┬───────┐ I
Artery I | | | I
I————+ >│Right atrium │Left Atrium │<—I
I I ├───v────┼────v──┤
I I—-| | |—
Vena cava │Right Ventricle │ Left Ventricle | I
I └──────-─┴───────┘ I
L________________________BODY<____________________I
Aorta

A

. Pulmonary vein
I———————->LUNGS—————————
Pulmonary I ┌──────-─┬───────┐ I
Artery I | | | I
I————+ >│Right atrium │Left Atrium │<—I
I I ├───v────┼────v──┤
I I—-| | |—
Vena cava │Right Ventricle │ Left Ventricle | I
I └──────-─┴───────┘ I
L________________________BODY<____________________I
Aorta

Right side is deoxygenated
Left side is oxygen rich

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Pathway through the human circulatory system

A

Deoxygenated blood enters lungs
Oxygen enters blood - CO2 leaves
Blood enters heart through pulmonary vein, into the left atria
Blood is pumped through the heart from left artria to left ventricle, via bicuspid valve
Blood is pumped out of left ventricle through Aorta and goes to rest of the body
Oxygen diffuses out of the blood and CO2 diffuses in
Blood enters right atria of heart through vena cava
Blood is pumped through heart from right artria to right ventricle, via tricuspid valve
Blood is pumped out of right ventricle, to return to lungs via pulmonary artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

4 key components of blood and their function

A

Red blood cells - small biconcave cells containing haemoglobin and have no nucleus to enable and maximise oxygen transport
Small in size, which guarantees passage even through tiny capillaries

White blood cells - large cells fight disease by making antibodies, or changing their shape to engulf pathogens

Platelets - tiny structures/fragments of cells that help blood to clot

Plasma - Made up of 90% water, fluid in which the other components of blood float within
Acts as a transport medium for digested food, waste products, hormones and antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Type of blood cell which is most common in the blood

A

Red blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Xylem

A

Transports water and mineral ions from roots to stem, leaves and flowers
End walls of dead xylem cells broken to allow water and dissolved minerals to move through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Function of phloem

A

Transports dissolves sugars from photosynthesis, and other soluble food molecules from leaves to all other areas of the plant

24
Q

Structure formed by xylem and phloem within the plant

A

Vascular bundle

25
Q

What tissue makes up bulk of plant in woody plants like trees

A

Xylem

26
Q

Experiment that can be done to easily visualise the xylem in plant tissue

A

Place celery in a jug of water containing food colouring
Leave for 24 hours
Cut slice of celery and veiw using magnifiying glass or light microscope

27
Q

Structure of xylem

A

Made from dead cells
No cell walls at ends of cells
Dead cells form tubes for water and mineral ions to flow
Xylem cellulose cell wall is thickened and stiffened with lignin to provide support

28
Q

Structure of phloem

A

Made of living cells
Cell walls connecting these cells do not completely breakdown creating sieve plates
Sieve plates allow dissolved sugars to pass
Connected cells form a tube allowing dissolved sugers to be transported

29
Q

Direction of flow in xylem

A

One way - Roots to leaves

30
Q

Direction of flow in the phloem

A

Two-way / bidirectional

31
Q

Tissue in a plant which would transport glucose

A

Phloem

32
Q

If a cross section was taken through the plant in the stem, where would you expect vascular bundle to be found

A

Bundles organised spherically in the cortex: cross section of the stem
Larger phloem at top of the bundle with smaller xylem tubes underneath

33
Q

If a cross section was taken through the plant in the root, where would you expect the vascular bundle to be found

A

Bundle in the centre of the root
Xylem in the centre of the bundle
Phloem around the outside of the xylem
Surrounded by ground tissue

34
Q

If a cross section was taken through the plant in the leaf, where would you expect the vascular bundle to be found

A

In spongy mesophyll layer
Xylem closest to palisade mesophyll layer (towards top of the leaf)
Phloem closest to the lower epidermis

35
Q

How vascular bundles provide support

A

In the leaf they form a network that supports softer tissue
In the stem they are loacted around the outer edge providing the stem with strength to resit bending
In the root they are found in the centre to enable the root to act as an anchor

36
Q

Transpiration

A

Movement of water through xylem

37
Q

Explain the transpiration stream

A

The stream of water though the plants xylem caused by the loss of water through the plants stomata in the wind
Water evaporates through stomata
Water potential gradient between leaves and stem - water moves into leaves by osmosis
Water potential gradient between stem and roots - water moves into stem by osmosis
Water potential gradient between roots and soil - water moves into root hair cells by osmosis

38
Q

What makes water vapour diffuse from the inside of a cell into the air

A

Water evaporates from inside leaf into leaf’s air spaces
Concentration gradient forms between the air inside leaf and the air outside the leaf

Water vapour diffuses from the area of high concentration or the air inside the leaf, to area of low concentration of air outside the leaf

39
Q

Structure of stomata and how they open and close to control gaseous exchange

A

Stomata are made up of 2 guard cells

When there is plenty of light and water the guard cells take up water by osmosis and become turgid,
The inner wall of the guard cell is thickened so the cell curves as it becomes turgid creating a gap between the two guard cells,
This gap is known as the stomata,
If conditions for photosynthesis are poor then the guard cells lose water and become flacid,
When the cells are flacid the gap between them closes

40
Q

Explain why the upper surface of many leaves is covered in a thick, waxy cuticle?

A

To prevent uncontrolled water loss
In hot environemnts this layer is very think and shiny

41
Q

Calculate rate of transpiration

A

Calculate the rate of movement of an air bubble using a potometer
Rate of movement = distance (mm) ÷ time (s)

Only an estimate as small volume of the water taken up by the shoot is used in leaves and not transpired

42
Q

Why does the plants need for CO2 increase the rate of transpiration in a plant.

A

Plants need glucose for respiration
Glucose is product of photosynthesis
Photosynthesis requires carbon dioxide and water
Plant must open stomata to enable the diffusion of carbon dioxide into the leaf
Open stomata allows water vapour to leave the leaf via diffusion
Lose of water from leaf increases rate of transpiration

43
Q

State the factors affecting the rate of transpiration

A

Light intensity = increase light, increase transpiration
Temperature = increase temperature, increase transpiration
Air movement = increase air movement, increase transpiration
Humidity = increase humidty, decrease transpiration

44
Q

What ringing experiment shows

A

A ring of bark is scraped away that also removes the phloem, exposing the xylem
Sugar then attempts to move down the stem but is stopped by the ring
This is demonstrated by a bulge of sugar forms above the ring
Suggesting that sugar moves down the stem in the phloem and sugar transported by the phloem

45
Q

Explain how potometer experiment can be used to measure rate of transpiration

A

Set up potometer making sure the stem is cut under water to ensure no air bubbles
Release an air bubble into the capillary tube
As the water evaporates from the leaves and moves into the stem the bubble moves towards the plant
Measure how fast the air bubble travels
Refill and repeat the experiment

46
Q

Difference in veins and arteries

A

Veins - blue - thin - carry blood to heart - valves along the length - wide lumen
Arteries - red - thick - carry blood away from heart - thick walls - narrow lumen diameter

47
Q

Pulmonary artery

A

Heart pumps out deoxygenated blood to the lungs through this artery.

48
Q

Pulmonary vein

A

Heart receives oxygenated blood from the lungs through this vein.
Coronary arteries have the same purpose:
The heart muscle is supplied with oxygenated blood through these arteries.

49
Q

Vena cava

A

Heart receives deoxygenated blood from the body through this vein.

50
Q

Aorta

A

Heart pumps out oxygenated blood to body through this artery

51
Q

Pathway through human heart

A

Blood enters the heart via atria
Once filled with blood, atria contract, forcing blood down into ventricles below
When the ventricles contract, they force blood to exit heart

52
Q

What happens when ventricles contract

A

they force blood to exit the heart

53
Q

Why might someone be fitted with an artificial pacemaker

A

group of cells in right atrium act as a pacemaker to control heart’s beating -
If there are irregular heart rates, can be corrected using electrical devices known as artificial pacemakers

54
Q

Difference between transpiration and translocation

A

Translocation is bidirectional (movement is both up and down the plant)
happens in the phloem NOT xylem

Unlike water transport (transpiration) which is unidirectional

55
Q

Sample card

A

The heart muscle is supplied with oxygenated blood through these arteries.

Biology OCR GCSE (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions